Our last journal club of the year was held at Dr. Dagnone’s house in beautiful patio weather (sorry for the delay in posting), where we discussed dexamethasone versus prednisolone for pediatric asthma exacerbations as well as the implications of the new high sensitivity troponin assay.
A Randomized Trial of Single-Dose Dexamethasone Versus Multi-dose Prednisolone for Acute Exacerbations of Asthma in Children Who Attend the Emergency Department
by John J. Cronin et al. published recently in the Annals of Emergency Medicine Journal
Dr. Heather White and Dr. Nick Cornell lead the group through a critical look at the recent article in Annals of Emergency Medicine regarding optimal management of acute asthma exacerbations in children. This was an intention to treat, randomized, and open label non-inferiority study looking at single dose dexamethasone compared to 3 days of prednisolone for treatment of acute asthma exacerbations in children. The conclusion was that dexamethasone (0.3mg/kg) was found to be non-inferior to a 3 day course of prednisolone (1mg/kg/d) as measured by the mean PRAM score on day 4.
The discussion was rich and the consensus seemed to lean away from practice changing impact. Several concerns were raised with the study including the generalizability to our practice environment and the bias introduced with open label methodology. The study was done in Ireland using a 1mg/kg dose of prednisolone, which is typically dosed at 2mg/kg here up front in the ED followed by 1mg/kg/day at home. The PRAM score was felt to be a reasonable surrogate for asthma control and severity, but the exclusion criteria was extensive and we thought that the differences in PRAM would be difficult to pick up. In the end, for a child with mild-moderate asthma exacerbation who does not tolerate prednisolone, single dose oral dexamethasone is a reasonable choice!
Derivation of a 2hr high-sensitivity troponin T algorithm for rapid rule-out of acute MI in ED chest pain patients
presented at CAEP 2016 by A McRae
The staff article this week was a very topical abstract presented at the 2016 CAEP conference by the University of Calgary’s Andy McRae. Dr. Colin Bell had a lot to add to Dr. Dagnone’s points after presenting a Grand Rounds on this topic earlier this year. Before going any further, the importance of knowing your own center was highlighted – at Kingston General Hospital, the lab is using the cTnI assay, which has increased sensitivity compared to the cTnT assay utilized in Calgary and the focus of the abstract.
The abstract described a study performed in Calgary to derive a 2-hr high sensitivity cTnT testing algorithm to rule out acute MI in ED chest pain patients. Their conclusion was that acute MI can be ruled out safely with a high sensitivity cTnT algorithm in 58.5% of chest pain patients within 2 hours of ED arrival. Apart from the obvious issue with a different assay, the logistics of the above mentioned time points in our ED, the definition of low risk chest pain and quantification of such, and the lower sensitivity of the algorithm for major adverse cardiac outcomes compared to acute MI made us all a little hesitant. The future sure looks promising, but we concluded that we’re yet ready for use of the 2-hr delta troponins across the board. It is probably okay for low risk chest pain patients, but the 6-hr test is definitely safer. Although there is lots more work to be done on this topic, the Calgary group has done a great job thus far and we’d like to congratulate them on the well deserved Grant Innes Research Award for top ranked CAEP abstracts this year in Quebec City!
Stop Colin or Damon next time you run into them to ask about their opinion – they have a wealth of information to share!
*as a useful side note, it came to light that a delta troponin (using our local cTnI assay) should only be considered different if it is >8